Dental matrix holder jaw



Patented May 9, 1933 UNITED stares WILLIAM E. HARPER, OF CHICAGO, ILLINOIS DENTAL MATRIX HOLDER JAW Application filed June 24, 1931. Serial Ii-To.y 546,484. i

My invention relates to new and useful improvements in jaws for dental matrix holders.

In the illing of approximal cavities it is most desirable to restore the anatomical form of the tooth without leaving any rough edges or projections between the tooth and the filling which would be susceptible of catching and holding food which would result in decay. This is now done by inserting a matrix band between the tooth to be filled and the next one, bending it around the subject tooth and wedging it in position by means of a matrix retainer having a pair of wedge shaped jaws adapted to be moved together by means of a screw. The jaws now used are of solid construction with a pair of concave faces. With such jaws forming the matrix the anatomical shape of the tooth is only apn proximated and the resulting filling must be tediously and diiiicultly ground in order to fashion the filling Hush with the tooth and eliminate the rough edges. The time required to so smooth the filling is of course chargeable to the patient and often such a charge is not justifiable, due to the financialV inability of the patient, and as a result the edges and definite angles are allowed to remain. As a result food will collect in these irregularities and decay the tooth.

The principal object of my invention is to provide a iexible jaw for use with dental matrix holders that Vwill conform the matrix hand to the anatomical form of the tooth so that the resulting filling will be flush with the tooth, obviating the objectionable irregularities above noted.

Another object is to provide an improved jaw which will enable adjoining teeth to be separated to normal position for filling where they have tipped together, closing the interdental space.

Numerous other objects and advantages will be apparent from the following detailed description.

In the accompanying drawing:

Fig. l is a plan view of a typical dental matrix holder equipped with jaws embodying my invention;

Fig. 2 isa side elevation of the device shown in Fig. l; t i 4' Fig. 3 is an enlargerl front perspective view of my improved jaw; and v Fig. 4 is lan enlarged rear perspective view.

Referring now more particularlyv to the drawing wherein j' like and corresponding parts are designated by similar reference characters throughout, ll and 2 are a pair of armspivoted togetherl at 3 and heldinopen position by means of the spring 4. VAn in' ternally threaded tube 5 is slotted to receive v the two arms nl and 2 and permit said arms to be moved together by means of screw member 6. At the end of each arm is pivotally mounted a aw 7 made of spring meta-l. Each `jaw 7 is fashioned from a single piece of metal which is bent to form a sleeve 8 for mounting the jaw on an arm of the M in a horizontal plane, the shoulders 9 abutf ting against the arm on which the jaw'fis mounted, thus limiting such movement so that the ends 11 of opposed -jaws are always substantially in alignment with each other. It should be noted that in this construction as the jaw is forced between two teeth the Y walls l0 are compressed toward each other but the exact contour of the toothvis much more accurately followed because :the sections 12 move independently of one another. Thus the matrix band is pressed firmly against the side, of the tooth atl all points adjacent the cavity to be filled following the 'Y anatomical form of the tooth, so that the resultant filling will be flush with the sidesA of the tooth.

I claim: l Y

1. A jaw formed of spring lmetalffor Vu 'sey with'a dental matrix holder comprising a pair of shoulders, a pair of walls converging from said shoulders to a point adjacent each other and extending therefrom parallel'to With a dental matrix holder comprising a pair of shoulders, a pair of Walls converging concavely from said shoulders to a point adj acenteach other and extending therefrom parallel to each other and means for mounting said jaw on an arm of said holder.

3. A jaw formed of spring metal for use with a dental matrix holder comprising tWo separated converging spring Walls forming a yieldable Wedge and divided into horizontal sections, and means for pivotally mounting said jaw on an arm ofa matrix holder.

4. rA javv formed of spring .metal for use With a dental matrix holder comprising a sleeve, a pair of shoulders, a pair of Walls converging v:from said shoulders and divided into independent sections, a pin adapted to it Within said sleeve Jfor pivotally mounting saidjavv on an arm of a dental matrix holder, said shoulders Vadapted to `abut against the said arm to limit pivotal movement. e I n Y 5. In combination, Va dental matrix holder comprising tvvo arms pivotally mounted to gether, meansr for'moving the ends of said arms together, oppositely disposed jaws mounted on lthe ends of said arms, each formed otspring metal and comprising a sleeve, a pair of shoulders, a pair of Walls converging from said shoulders and divided vinto independentsections, a pin adapted to 'fit Within said sleeve for pivotally mounting said jaw on an .arm of said holder, said shoulders adapted to abut against said arm to limit pivotal movement. y

6. A jaw formed of spring metal for use With a dental matrix holder rcomprising a pair of shoulders, a pair of Wallsconverging from said shoulders and divided into independent horizontal sections and means for pivotally mounting said jawk on anV arm of the matrix holder.

7. A jaw formed of spring metal for use with a dental matrix holder comprising a pair of shoulders, a pair-of Walls converging from said shoulders to a point adjacent each other and extending therefrom parallel to one another, said Walls divided into horizontal sections and means for mounting said jaw on an arm of said holder.

8. A jaw formed of spring metal for use with a dentalmatrix holder comprising a pair of shoulders, a pair of Walls converging concavely from said shoulders vto a point ad jacenteach other and extending therefrom parallel to each other said Walls divided into horizontal sections, and means for pivotally mounting said jaw on said holder.

9. A jaw formed of a single piece of spring metalfor use With a dental matrix holder comprising a pair of Walls divided into horizontalseetions parallel at the point WILLIAM E. HARPER. 

